i know this suggestion will be slated but a sure fire way to get rid quickly is to put some lime down on the run they use, they will always go the same route. usually staying close to walls,fences etc, once the lime is on them they will clean themselves and therefore ingest poison, not nice, but some farmers use this method. I would put some good quality traps down or call in a pest control officer, your local council will advise you or may even do the job for you. good luck, Ray